The present invention relates to a microsurgical instrument, in particular to a ophthalmologic instrument for use especially but not exclusively in surgery of the retina of an eye of the type having a housing configured as a handle and an axial probe operatively connected to the housing, wherein the probe is configured for receiving an axially extended rod with a head piece configured for microsurgical procedures.
The present invention concerns problems that arise in surgical treatment of retinal diseases, as for example resulting from hypertonia, or other vascular changes. In a typical disease where vascular changes are the origin, a venous branch occlusion (phlebemphraxis) can occur at the crossing point of an artery and a vein. In the area of the crossing the artery and the vein are surrounded by a substantially transparent skin sheath or membrane and the artery which overlays the vein can press on the vein such that the vein may be squeezed off in such a manner that an occlusion occurs resulting in an obstruction of the blood flow.
Experiments have shown that by surgically cutting or removing this skin membrane by means of an ophthalmologic instrument, venous branch occlusions can be substantially eliminated or prevented. During microsurgery the transparent skin membrane is removed and the artery separated from the vein for blood flow to resume in this area. When using the conventional microsurgical instruments separation of the artery from the vein may result in the injury to the artery or injury to the underlying vein. Furthermore, the artery may be “pinched” by the microsurgical instrument during separation leading to trauma or injury of these delicate blood vessels.
It would thus be desirable and advantageous to provide an improved surgical instrument with which these shortcomings can be overcome.
When carrying out this micro surgery it is important that the artery is being moved away from the vein by a small pull motion in such a manner that the vein is being laid free but that the pull motion on the artery is carried out without the artery being squeezed off, pinched or constricted in any way.